Optical fiber logging cable seal pod

Abstract

The application discloses a kind of optical fiber logging cable sealing bin, solve the existing optical fiber end in downhole sealing problem.Technical scheme includes optical fiber cable and cylinder, the optical fiber cable is by the optical fiber part in optical fiber protection pipe and the cable armoring steel wire part outside optical fiber protection pipe, the cylinder front section is equipped with cable locking structure, rear section is equipped with sealing bin;The optical fiber protection pipe end equipped with optical fiber part passes through the cylinder front end, cable locking structure stretches into sealing bin, wherein, the optical fiber part in the optical fiber protection pipe is placed in sealing bin;Cable armoring steel wire part is fixedly connected with the cable locking structure.The application structure is simple, easy to install, while meeting the sealing and connectivity requirements of optical signal optical fiber of optical fiber cable.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of petroleum logging instrument, in particular to a kind of optical fiber logging cable sealing bin. BACKGROUND

[0002] Traditional electronic sensor logging method cannot work in the harsh environment (such as high temperature, high pressure, corrosion, geomagnetic and telluric interference) downhole, while optical fiber sensor can overcome these difficulties, optical fiber cable with anti-electromagnetic interference, high sensitivity, high spatial resolution and other characteristics, in recent years in domestic petroleum industry has entered a period of rapid growth. But the optical fiber insulation is very high for logging requirements, once the optical fiber is in contact with the liquid in the well, the optical fiber transmission loss increases sharply, however, in the use of optical fiber cable, it is very easy to contact the optical fiber with the liquid in the well, which leads to normal logging operation, even the optical fiber cable is damaged and scrapped and economic loss. SUMMARY

[0003] The purpose of the present application is to solve the above technical problems, provide a kind of optical fiber logging cable sealing bin with simple structure, easy to install, while meeting the sealing requirement of optical fiber cable optical signal optical fiber.

[0004] The technical scheme of the present application is an optical fiber logging cable sealing bin, comprising an optical fiber cable and a barrel, the optical fiber cable is composed of an optical fiber part located in an optical fiber protection tube and a cable armored steel wire part located outside the optical fiber protection tube, the front section of the barrel is provided with a cable locking structure, and the rear section is provided with a sealing bin;

[0005] The end of the optical fiber protection tube with the optical fiber part passes through the front end of the barrel and the cable locking structure and extends into the sealing bin, wherein the optical fiber part in the optical fiber protection tube is placed in the sealing bin; the cable armored steel wire part is fixedly connected with the cable locking structure.

[0006] The rear end of the sealing bin is provided with a sealing cover.

[0007] The sealing cover and the inner wall of the barrel are connected by screw thread, and a sealing ring is arranged on the side surface.

[0008] The sealing bin is filled with silicone grease.

[0009] The cable locking structure comprises a cable locking sleeve, a first pressing block, a sealing block and a second pressing block which are pressed to the front end of the barrel in sequence; the optical fiber part of the optical fiber cable passes through the cable locking sleeve, the first pressing block, the sealing block and the second pressing block in sequence and enters the sealing bin, and the cable armored steel wire part of the optical fiber cable is fixedly wound on the cable locking sleeve.

[0010] The first pressing block and the second pressing block are connected with the inner wall of the barrel by screw thread.

[0011] The sealing bin is internally provided with an optical fiber fixing device.

[0012] The optical fiber fixing device comprises a fixing body arranged on the inner wall of the barrel, the top surface of the fixing body is provided with a plurality of slot holes for inserting the optical fiber part of the optical fiber cable, and the top surface of the fixing body is further provided with a fixing compression block, and the two are connected through a fixing screw.

[0013] In view of the problems in the background art, the inventors have made the following improvements:

[0014] 1) The optical fiber part of the optical fiber cable is sealed by the sealing unit, and considering the particularity of the downhole working condition, the cable armored steel wire part also needs to be effectively fixed; the front section of the barrel of the sealing unit is provided with a cable locking structure for fixing the cable armored steel wire part, so as to realize fixed connection with the barrel; the rear section of the barrel is provided with a sealing bin, and the optical fiber part of the optical fiber cable is placed in the sealing bin, so as to ensure the sealing state of the optical fiber under any condition.

[0015] 2) Considering the sealing effect, the rear end of the sealing bin is provided with a sealing cover, the sealing effect in the sealing bin is ensured by using the sealing cover, so that the optical fiber part can be well sealed in the sealing bin and cannot contact the liquid in the well, thereby effectively avoiding the entry of the downhole liquid into the optical fiber protection tube.

[0016] 3) The sealing bin is internally provided with an optical fiber fixing device, the end part of the optical fiber part is fixed by using the optical fiber fixing device, so that the optical fiber remains in a relatively static state, meanwhile, the gap part in the sealing bin is filled with silicone grease, the sealing space is further closed to prevent the entry of the downhole liquid, and the optical fiber part is fixed to avoid damage of the optical fiber part during movement, and the sealing effect is further improved.

[0017] The present application has the advantages of simple structure, easy disassembly and assembly, and can meet the sealing and connection performance of the optical signal optical fiber of the optical fiber cable, and can ensure the sealing of the optical fiber under any condition in the well, and has a wide market application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a structural schematic view of the present application.

[0019] Figure 2 It is a schematic view of the cable locking sleeve on which the cable armored steel wire part is wound.

[0020] Figure 3 It is a structural schematic view of the optical fiber fixing device.

[0021] 1-cylinder, 2-cable locking sleeve, 3-first pressing block, 4-sealing block, 5-second pressing block, 6-sealing cover, 7-optical fiber protection tube, 8-steel wire armor portion, 9-sealing chamber, 10-optical fiber portion, 11-optical fiber cable, 12-sealing ring, 13-grease injection hole, 14-optical fiber fixing device, 14.1-fixing body, 14.2-slot hole, 14.3-fixing pressing block, 14.4-fixing screw. DETAILED DESCRIPTION

[0022] The application will be further explained in conjunction with the accompanying drawings:

[0023] Referring to Figure 1 , the application comprises a cylinder 1 and an optical fiber cable 11, the front section of the cylinder 1 is provided with a cable locking structure, and the rear section is provided with a sealing chamber 9.

[0024] The end of the optical fiber cable 11 with an optical fiber protection tube 7 extends into the sealing chamber 9 in the rear section through the front end of the cylinder 1 and the cable locking structure in the front section, wherein the optical fiber portion 10 of the optical fiber cable 11 is placed in the sealing chamber 9, and the cable steel wire armor portion 8 is fixedly connected with the cable locking structure.

[0025] The cable locking structure comprises a cable locking sleeve 2, a first pressing block 3, a sealing block 4 and a second pressing block 5 which are sequentially pressed towards the front end of the cylinder 1; referring to Figure 2 , the cable locking sleeve 2 has a hollow structure, the optical fiber portion 10 of the optical fiber cable 11 sequentially passes through the cable locking sleeve 2, the first pressing block 3, the sealing block 4 and the second pressing block 5 to enter the sealing chamber 9, and the cable steel wire armor portion 8 of the optical fiber cable 11 is fixed by winding around the cable locking sleeve 2, and the winding manner is not particularly limited, for example, the steel wire armor portion 8 is bent along the top surface and side surface of the upper end of the cable locking sleeve 2, then downwardly penetrates into the hole in the lower section of the cable locking sleeve 2, and then the steel wire is bent upwardly along the side surface of the lower end of the cable locking sleeve 2.

[0026] The first pressing block 3 and the second pressing block 5 are both connected with the inner wall of the cylinder 1 by screw threads. After the first pressing block 3 is screwed with the cylinder 1, pressure is applied to the cable locking sleeve 2, so that part of the steel wire armor portion 8 is embedded in the cable locking sleeve 2 and is tightly fixed with the cylinder 1, thereby ensuring that the cylinder 1 and the optical fiber cable 11 do not separate. After the second pressing block 3 is screwed with the cylinder 1, force is applied to the sealing block 4, and the sealing block 4 is made of elastic material (such as rubber), so that the sealing block 4 is deformed under the extrusion force, tightly contacts with the optical fiber protection tube 7, and achieves the sealing effect.

[0027] The rear end of the sealing chamber 9 is provided with a sealing cover 6, preferably, the sealing cover 6 is connected with the inner wall of the cylinder 1 by screw threads, and the side surface is provided with a sealing ring 12.

[0028] The sealing bin 9 is provided with a fiber fixing device 14 and filled with silicon grease, which can be injected through the grease injection hole 13 provided on the corresponding cylinder 1 of the sealing bin 9, see Figure 1 The two grease injection holes 13 are symmetrically arranged, and the grease injection hole 13 after the grease injection operation is sealed by the jackscrew.

[0029] See Figure 3 The fiber fixing device 14 is used for fixing the end of the fiber part and includes a fixing body 14.1 provided on the inner wall of the cylinder, the top surface of the fixing body 14.1 is provided with a plurality of slot holes 14.2 for inserting and fixing the fiber part 10 of the fiber cable, and the top surface of the fixing body 14.1 is further provided with a fixing and pressing block 14.3, and the two are connected through a fixing screw 14.4.

[0030] The present application can be installed in a logging tool string, for example, when the fiber logging is conveyed by a tractor, the present application can be installed on the cable male head; when the fiber logging is hydraulically pumped, the present application can be installed in the pumping device, and all can meet the sealing performance requirements of the fiber, and since the diameter of the cylinder 1 can be made smaller, the sealing bin of the present application will not be stuck in the well, and the smooth operation of the fiber cable operation can be ensured. At present, 23 wells of the fiber logging conveyed by the tractor and 27 wells of the hydraulic conveying logging have been completed, the sealing effect is good, even if the sticking occurs, the fiber will not be in contact with the liquid in the well.

Claims

1. A sealed housing for fiber optic logging cables, comprising a fiber optic cable and a cylindrical body, characterized in that, The optical fiber cable consists of an optical fiber portion located inside the optical fiber protection tube and a cable armor steel wire portion located outside the optical fiber protection tube. The front section of the cylinder is provided with a cable locking structure, and the rear section is provided with a sealed chamber. The rear end of the sealed chamber is provided with a sealing cover. The end of the fiber optic protective tube containing the fiber optic portion passes through the front end of the cylinder and the cable locking structure and extends into the sealed chamber. The fiber optic portion of the fiber optic protective tube is placed in the sealed chamber, and the gap in the sealed chamber is filled with silicone grease. The cable armor steel wire portion is fixedly connected to the cable locking structure. The cable locking structure includes a cable locking sleeve, a first pressing block, a sealing block, and a second pressing block that are sequentially pressed against the front end of the cylinder; the optical fiber portion of the optical fiber cable passes sequentially through the cable locking sleeve, the first pressing block, the sealing block, and the second pressing block into the sealing chamber, and the sealing block is made of an elastic material; the cable armor steel wire portion of the optical fiber cable is wound and fixed on the cable locking sleeve, and the first pressing block and the second pressing block are connected to the inner wall of the cylinder by threaded connections; The sealed chamber is equipped with an optical fiber fixing device, which includes a fixing body on the inner wall of the cylinder. The top surface of the fixing body has multiple slots for inserting the optical fiber portion of the optical fiber cable. The top surface of the fixing body is also equipped with a fixing clamping block, and the two are connected by fixing screws.

2. The fiber optic logging cable sealing chamber as described in claim 1, characterized in that, The sealing cap is connected to the inner wall of the cylinder by a threaded connection.

3. The fiber optic logging cable sealing chamber as described in claim 1, characterized in that, The sealed chamber is filled with silicone grease.

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